NEIL DEGRASSE TYSON: He was designed by an engineer who's
building sociable robots.

WOMAN (NEEDS NAME AND IDENTIFIER): You're such a cute little robot.

NEIL DEGRASSE TYSON: Robots that one day may even become our
friends, with feelings and emotions. Wait a minute, an emotional robot?

CYNTHIA BREAZEAL (Massachusetts Institute of Technology): I do
think, in time, people will have, sort of, relationships where they might feel
that it is a friendship, but it's going to be of a robot-human kind.

MATT BERLIN: Can you find Elmo?

NEIL DEGRASSE TYSON: All that and more on this episode of NOVA
scienceNOW.

Google is proud to support NOVA in the search for knowledge: Google.

Major funding for NOVA scienceNOW is provided by the National Science
Foundation, where discoveries begin.

And The Howard Hughes Medical Institute, serving society through biomedical
research and science education: HHMI.

Additional funding is provided by the Alfred P. Sloan Foundation, to portray
the lives of men and women engaged in scientific and technological
pursuit.

And the George D. Smith Fund.

Major funding for NOVA is also provided by the Corporation for Public
Broadcasting, and by PBS viewers like you. Thank you.

MASS EXTINCTION

We all know that Earth is brimming with life, all kinds of life, as it has
been for most of the last 600 million years. But every now and then, something
happens. Earth becomes a very unfriendly place, and most life can't survive.
It's called mass extinction. We know it's happened over and over again, in the
deep past, but we don't always know why.

In a remote Nevada desert, a team of investigators is trying to solve an
old murder mystery.

SAM BOWRING OFF CAMERA: So yeah, this looks good.

NEIL DEGRASSE TYSON: And I mean old; the victims were knocked
off about 250 million years ago, in an ancient mass extinction.

SAM BOWRING: Based on the fossil record, this is probably the most
profound extinction of animal life.

DOUGLAS H. ERWIN (Smithsonian Institution): There's no other
time, in the last 600 million years, that you wipe out 95 percent of all the
species in the ocean.

NEIL DEGRASSE TYSON: Geologist Sam Bowring and paleontologist
Doug Erwin think this hillside might be a scene of the crime. They're looking
for clues to find out what caused the mysterious end of the geological time
period known as the Permian.

PETER D. WARD (University of Washington): The Permian world, and
the extinction that ended the Permian world, really reset the nature of life on
this planet.

NEIL DEGRASSE TYSON: Paleontologist Peter Ward has spent years
collecting fossils from the strange time of the Permian.

PETER WARD: Permian would have looked very different to us. Let's say we
go back there, we look around: no flowers, no flowering plants; there's not
even dinosaurs. This is before dinosaurs. There probably wasn't a single animal
on the planet with fur.

PETER WARD: This is a mammal-like reptile, probably small-dog size. This
animal is a carnivore. It really has a dog-like appearance. We can see this
great big piercing tooth.

NEIL DEGRASSE TYSON: Clearly making him a predator.

PETER WARD: Yeah, but this entire group dies out in the extinction
itself.

NEIL DEGRASSE TYSON: There were creatures right out of a
science fiction movie, like plant-eating Lystrosaurs, and, ruining their day,
monstrous Gorgons.

The extinction ravaged the oceans, once filled with exotic animals. But
then, about 250 million years ago, almost everything on sea and land died. So,
who's the culprit? What could kill off so much life? Could it be climate
change? Global warming? Or would you need something from out of this
world?

There've been at least five major extinctions in the last 600 million
years. Most of us have heard of one, at the close of the Cretaceous, ending of
the reign of the dinosaurs. That happened about 65 million years ago, when an
asteroid the size of Mount Everest slammed into our planet, leaving a giant
crater near what is now Mexico.

So we know the dinosaurs were knocked off by a giant rock that fell from
the sky; and we also know that these rocks hit Earth from time to time; so when
we try to figure out what caused all the mass extinctions of the past,
shouldn't it just make sense that they'd also be caused by comets and
asteroids?

PETER WARD: I went into this controversy fully expecting to find all the
evidence for impact. And at the end of the Cretaceous, we see this. We see lots
of comet material or asteroid material.

NEIL DEGRASSE TYSON: Not to mention the crater, of
course.

PETER WARD: Not to mention the crater, least of all the crater.

NEIL DEGRASSE TYSON: So you've got the smoking gun—the
gun, and the bullets, and, of course, the dead bodies, I guess.

PETER WARD: Well, the only thing we have at the end of the Permian
is...are the dead bodies.

NEIL DEGRASSE TYSON: So, if asteroids and extinction don't
necessarily go hand in hand, what does Earth do with all those asteroids that
come our way?

SAM BOWRING: The Earth is hit by asteroids all the time—big
ones—doesn't cause mass extinction. Why not look for something a little
bit different?

NEIL DEGRASSE TYSON: But where can we find that
something?

SAM BOWRING: Here's the boundary, right here.

NEIL DEGRASSE TYSON: This Nevada hillside might be one of a
few existing Permian crime scenes in North America, but the team must date the
rocks, to see if they're the same age as the extinction.

SAM BOWRING: Timing is everything. You have to have rocks that can be
dated precisely.

NEIL DEGRASSE TYSON: Back at the lab, the team breaks down the
rock. Rare elements reveal when the rock formed. The results? About 250 million
years old.

So this is a crime scene. But where's the killer? What kind of a disaster,
other than an asteroid, could destroy so much life?

One of the prime suspects is an ancient group of volcanoes, now dormant,
whose remains lie in eastern Russia. Known as the Siberian Traps, these were no
ordinary volcanoes.

DOUG ERWIN: Most people, when they think of volcanoes, think of Mount
St. Helens or Mount Pinatubo. That's nothing like these volcanic episodes.

NEIL DEGRASSE TYSON: The Siberian Traps oozed lava for up to a
million years, smothering an area about the size of the continental United
States, in some places, over a mile deep.

SAM BOWRING: That is a lot of lava.

NEIL DEGRASSE TYSON: Sure is. But still, the lava was in
Siberia, not in the rest of the world, not in the whole ocean. So why would
almost everything on Earth die?

Marine geochemist Lee Kump thinks he's found the answer. The key is in how
big volcanoes could change the environment, including the chemistry of the
Permian ocean.

To test his idea, he designed a computer model to simulate the Permian
world.

LEE KUMP (The Pennsylvania State University): So the model starts
out like a weather forecasting model or a climate model: it has the winds;
there's the ocean currents that are driven by those winds; there are
temperature variations. But the model also has life in it.

It all starts with the Siberian Traps, but the trigger is not the incessant
flow of lava, which would burn and bury any life nearby. No, the real culprits
are the gases that the volcanoes spew into the atmosphere, including one we've
all heard of lately, carbon dioxide.

LEE KUMP: Carbon dioxide that's spewing out of these volcanoes is a
greenhouse gas.

NEIL DEGRASSE TYSON: Greenhouse gases trap the Sun's heat in
our atmosphere, forcing the whole Earth to warm up. Of course, that's global
warming. But it doesn't end there. Global warming would have heated the Permian
ocean, and when it did, ocean chemistry would have changed dramatically.

LEE KUMP: There's a difference between warm and cold water. Cold water
can hold more gas than can warm water. And so this is, fundamentally, why we
drink champagne and beer and soda cold, rather than warm.

NEIL DEGRASSE TYSON: What's true for champagne, beer or soda
is also true for the ocean and one of its most important gases, oxygen.

LEE KUMP: Cold water can hold a lot of oxygen. Warm water can't hold
much oxygen.

NEIL DEGRASSE TYSON: And if water loses its oxygen, things can
go from bad to worse.

Lee and his research team have seen this firsthand, at Green Lakes in
central New York State. This lake is narrow and deep, and there's little wind.
As a result, the deeper waters have lost their oxygen.

LEE KUMP: It's safe to swim in this lake, as long as you stay above 70
feet.

NEIL DEGRASSE TYSON: Below that, the oxygen-free water has
attracted a deadly form of bacteria.

LEE KUMP: There are bacteria that can thrive under those conditions, and
those bacteria produce hydrogen sulfide. Hydrogen sulfide is a very toxic
substance, and so, the deep part of this lake is highly poisonous.

NEIL DEGRASSE TYSON: It's also bright pink.

LEE KUMP: Here you go.

When we bring these samples to the surface, of course, they're rich in
hydrogen sulfide. They stink like rotten eggs, and they're poisonous.

KATJA (Research team member): Oh, that stinks! Yuck.

NEIL DEGRASSE TYSON: The bright pink color comes from another
microbe, purple sulfur bacteria, that thrive in hydrogen sulfide. Bacteria like
these can leave chemical traces in ancient rocks. In fact, such traces have
been found in some rocks dating to the Permian extinction.

For Lee, it's a sign that the Permian ocean might have resembled this
poisonous lake.

LEE KUMP: This lake is a microcosm of what we think the ocean was like
in the late Permian.

NEIL DEGRASSE TYSON: According to Lee's computer model, over
time, the oceans would have become so full of hydrogen sulfide that in some
spots, the deadly gas would have bubbled right out into the atmosphere, killing
millions of creatures, not only in the sea, but also on the land.

The deadly microbes under suspicion aren't rare. They thrive wherever
there's water and no oxygen, as Peter Ward showed me, on an ordinary beach, at
low tide.

PETER WARD: Even here—we're on a beach in Seattle—we only
have to go down about two inches to see, sort of, the next step, in what we
think is this extinction mechanism. There. Smell that.

NEIL DEGRASSE TYSON: Ooh, yeah, smells like rotten
eggs.

PETER WARD: Rotten eggs. So, this is hydrogen sulfide from bacteria in
the sediment. So, let's just take those bacteria, put them in the ocean and
have untold tons of them.

NEIL DEGRASSE TYSON: Having...have it run amok.

PETER WARD: Everywhere. The oceans are bacteria filled. And they're
producing that same nasty rotten-egg smell, but in sufficient quantity, not
just to kill stuff in the water, but enough goes in the atmosphere to kill land
life.

NEIL DEGRASSE TYSON: So it burps up this noxious gas.

PETER WARD: Big bubbles come out of the oceans, and it will kill off
animals and plants.

NEIL DEGRASSE TYSON: And so, an extinction that began in the
ocean works its way to the land.

PETER WARD: Exactly. It's horrible.

NEIL DEGRASSE TYSON: So it starts with volcanoes spewing
carbon dioxide; next step: global warming. The oceans heat up and lose their
oxygen, nasty bacteria take over, burping out lots of poisonous gas. End
result? Mass extinction.

Peter Ward is convinced this was the scenario, not just for the Permian,
but for most of the other big extinction events, too.

PETER WARD: What really looks like a universal way that this has
happened is this global warming, leading to this terrible gas chamber
atmosphere killing off life in the ocean and land. It's not so much stuff from
space that gets you; it's your own planet.

NEIL DEGRASSE TYSON: The Nevada rocks offer some support for
the idea, at least for the Permian. This whole area was once at the bottom of
an ocean, and tests on the rocks have revealed that, in the years leading up to
the extinction, the deep ocean water here had lost its oxygen.

The next step will be to probe these rocks for telltale signs of that nasty
bacteria and hydrogen sulfide.

Until there's more evidence, the detectives won't all agree that the case
is closed. But these experts are convinced that Earth's own environment could
be the perpetrator of a mass extinction, whether it's 250 million years ago or
right now.

SAM BOWRING: We know, for a fact, that there have been huge changes in
the environment, in climate change. That could happen again today, no asteroids
required. The Earth is an incredibly dynamic place, lots happening. We have to
understand those changes if we want to survive.

1918 FLU

NEIL DEGRASSE TYSON: With winter come fears of the flu, and
sometimes the flu can be deadly, especially the bird flu. You've all heard of
it. It's a virus that people catch from birds like chickens. It's already
killed hundreds of people.

Fortunately, this bird flu does not spread easily from person to person,
but if it evolves a way to do that, we could be in big trouble.

Correspondent Chad Cohen met up with folks who are trying to stop that from
happening by taking a closer look into our past, at the most deadly viral
outbreak ever.

CHAD COHEN (Correspondent): Whatever scary things are
lurking in the back of your freezer, I'll venture a guess you've got nothing on
Terrence Tumpey. Getting into his deep freeze, at the CDC in Atlanta, is like
prepping for a spacewalk.

Frozen inside, sits a tiny vial of what might be the deadliest pathogen in
history, a virus that hadn't been seen in almost 90 years, the 1918
flu—until Tumpey brought it back from the dead.

IAN WILSON: 1918 was the worst pandemic we've seen for any virus, and
this killed, probably, at least 50 million people worldwide.

CHAD COHEN: In 1918, flu took three times as many lives as all
of World War I.

IAN WILSON: So the question is, "Why was it, in 1918, so different? Why
did it cause so many excess deaths, compared to other pandemics?"

CHAD COHEN: And could a flu that deadly strike again?

We do know where all flu viruses get their start: in the digestive tracts
of birds.

TERRENCE TUMPEY: They just happily co-exist there, not causing disease,
for the most part, in wild birds.

CHAD COHEN: But every once in a while, an ordinary bird flu
changes.

TERRENCE TUMPEY: It's a mistake in nature. These viruses actually get
out and infect other hosts.

CHAD COHEN: Hosts, like people. That's what scientists think
may have happened in 1918.

IAN WILSON: The thought was that, in 1918, the virus did cross the
species barrier and directly infect humans.

CHAD COHEN: That's one theory, at least. And when a virus that
begins in birds gains the ability to pass from human to human, infecting our
lungs, spreading through coughs and sneezes, no one's immune because it's never
been around before. And that's when a pandemic occurs.

We're hearing a lot, recently, about the threat of a new pandemic, the
avian flu. It's quite lethal, transmitted through close contact with birds, to
people who work and live near birds.

TERRENCE TUMPEY: Fortunately this virus has not figured out how to
efficiently transmit itself from human to human.

The question is will they ever be able to? And if so, how? And when this
virus does strike, why does it kill?

Terrence Tumpey believes he can find the answers by experimenting with a
flu that transmitted and killed very well, the 1918 virus.

TERRENCE TUMPEY: By having this in hand, we can actually try to
understand better how these pandemic flu viruses work.

CHAD COHEN: There was just one small problem: the 1918 virus
hadn't been around for nine decades.

JEFFREY K. TAUBENBERGER (Armed Forces Institute of Pathology): No
one had ever been able to study the 1918 virus, this horrible killer virus,
because there were no isolates.

CHAD COHEN: No living samples. But biologist Jeffrey
Taubenberger, searching through preserved tissue samples of World War I
soldiers, was able to recover the 1918 flu's genetic code. Somewhere, buried
within, are instructions that gave it the ability to kill. But where?

TERRENCE TUMPEY: Unfortunately, when you look at the genetic sequence,
the blueprint of this virus, there's no smoking gun that tells us that this
particular virus is lethal.

CHAD COHEN: Tumpey couldn't find an answer by simply reading a
recipe for the 1918 flu virus, he needed to experiment with the real
thing.

TERRENCE TUMPEY: We felt like it was important to actually reconstruct
this virus.

CHAD COHEN: That's right, he said, "reconstruct," rebuild the
1918 flu from scratch, one of the most lethal viruses we've ever known.

Using Taubenberger's recipe and a technique called reverse genetics,
scientists at the Mount Sinai School of Medicine added all the chemical
building blocks in the right order and the right amounts, and it worked.

They created a living 1918 virus so nasty that when Tumpey exposed lab mice
to it, they were all dead in just three days.

TERRENCE TUMPEY: I was quite surprised. I didn't anticipate that they
would die that quickly. That was very quick.

CHAD COHEN: And it was just what happened to humans in 1918.
Unlike normal flu strains, which can only infect high in the respiratory tract,
the 1918 virus attacked tissue deep in the lungs, as well, and that's a
vulnerable spot.

CHAD COHEN: The 1918 flu so badly inflamed those areas of its
victims' lungs that many died through suffocation. And, as it happens, that's
just how the avian flu kills, too.

TERRENCE TUMPEY: Those are important characteristics and similarities
among the 1918 virus as well as the avian virus.

CHAD COHEN: So, these two deadly viruses attack similar parts
of the lungs, but that still doesn't answer the biggest question: "Will the
avian flu ever transmit from people to people like the 1918 virus did?"

Well, first, let's back up a little bit. How does flu infect us in the
first place?

So this is what flu looks like under a microscope?

TERRENCE TUMPEY: Electron microscope, yeah.

CHAD COHEN: An actual flu virus, but for our purposes, let's
represent a virus by this unpleasant fellow.

For all his nastiness, he isn't all that complex. In fact, he only has
eight genes. We, by comparison, have more than 20,000.

We're going to look at two of these eight flu genes: one, because it's
responsible for getting the virus into a cell, and the other, for getting it
out again.

Flu gets into cells with the "hemagglutinin" gene.

IAN WILSON: So, in order to penetrate cells, you could imagine that the
hemagglutinin was sort of like a key.

CHAD COHEN: A key, which we'll refer to simply as "H." And
that key unlocks the cell, so that the virus can get inside.

TERRENCE TUMPEY: If it gets into your cell, it will take over the
machinery of the cell and start making more copies of itself.

CHAD COHEN: But now the virus has a problem. These copies are
stuck to that cell. That's where the other gene comes in. It's called
Neuraminidase, or "N," for short.

TERRENCE TUMPEY: Neuraminidase is critical for release.

CHAD COHEN: Getting back out?

TERRENCE TUMPEY: Getting back out.

CHAD COHEN: The virus copies use N to cut themselves free. And
now each of them, armed with their own Hs and Ns, are off to infect more cells.

In birds, there are 16 different kinds of H genes and nine N genes. Every
flu is some combination of these. Humans have only caught a few.

The Hong Kong flu, which killed nearly a million people when it broke out,
in 1968, gets in with H3 and out with N2. So it's called H3N2. In 1918, the
virus, which killed 50 million people, was H1N1. Now there's the avian flu
that's got everyone so worried, and it has a new combination of Hs and Ns:
H5N1.

The avian flu's H key, or hemagglutinin gene, can open the lock between
birds and people, that is, transmit from birds to humans. But it still cannot
open the lock between people and spread from one person to
another—yet.

But here's the problem: once it's in our bodies, the hemagglutinin gene can
change. It's as if it can fit the lock, but it can't turn it, which would be
great, if it stayed that way. But a virus's genetic recipe constantly changes,
or mutates, as scientists like to say. And if just the right changes take place
in the hemagglutinin gene, those changes could open the lock, allowing it to
spread between people.

But exactly what are those changes?

Going back to Taubenberger's recipe for the 1918 virus, Ian Wilson and his
colleagues at the Scripps Research Institute found the answer to what the 1918
virus may have needed to spread between humans. They pinpointed two changes, or
mutations.

IAN WILSON: Only two mutations were sufficient to change the virus's
hemagglutinin to adapt to human receptors.

CHAD COHEN: So could those same two mutations in the avian
flu's hemagglutinin gene allow it to spread between humans also?

To find out, they tried those same two mutations.

IAN WILSON: To our surprise, we found that, in fact, we couldn't very
easily change it with the mutations that occurred in 1918. So that suggests
that it might actually be a little bit more difficult, and it might take a
little bit more time, for an H5N1 virus to be able to adapt to human lung
cells.

CHAD COHEN: And that's good news. The Scripps team believes
the H5N1, or avian, flu doesn't seem to adapt easily, so that people can infect
other people.

Back at the CDC, Tumpey is taking a different approach to find out why
these viruses are so deadly. Instead of experimenting with tiny variations in a
flu gene, Tumpey is testing entire genes. He's looking at each of the 1918
virus's eight genes, one by one by one, to see which ones caused it to be so
lethal and which ones should be the target of new antiviral drugs. He started
with that H key gene.

He took one from his 1918 virus and put it in an ordinary seasonal flu.

TERRENCE TUMPEY: ...a contemporary influenza strain that doesn't kill,
and, all of a sudden, it was lethal.

CHAD COHEN: And when he did the reverse, took the H key from
an ordinary flu and put it on a 1918 virus...

TERRENCE TUMPEY: The virus was no longer lethal; it didn't cause
disease.

CHAD COHEN: So all signs seem to point to the H key, or H.A.,
as scientists call it, as being, at least partly, responsible for lethality.

TERRENCE TUMPEY: Well, there's something very intriguing about the
H.A.

CHAD COHEN: So intriguing that, now, Tumpey is planning to do
something pretty radical: put the hemagglutinin gene from the 1918 flu virus
into the avian flu virus, to see if he can create an avian flu virus that can
spread from person to person.

You want to combine H1, 1918, with H5? What's going on there?

TERRENCE TUMPEY: I think it will be important, as a set of
experiments to understand how H5N1 works. And by mix-and-matching it with genes
from a virus that actually did that quite well, the 1918 virus, we are hopeful
that we can figure that out.

I think, from a scientific point of view, this is the only way to
understand how these pandemic viruses work.

CHAD COHEN: Tumpey is one of the few people in the world who
has the clearance to work with a live 1918 flu virus.

TERRENCE TUMPEY: So if we can figure out how to slow it down, studying
this virus as a model virus, then perhaps we'll advance our knowledge on the
avian H5N1 virus as well. Maybe we can figure out how to stop it.

CHAD COHEN: If Terrence Tumpey has his way, the virus that
took so many lives in the past may help prevent another from taking more lives
in the future.

PROFILE: CYNTHIA BREAZEAL

NEIL DEGRASSE TYSON: Life, today, revolves around technology,
and when something goes wrong, it can be so frustrating. Sometimes, you just
wish machines could be a bit more helpful—nicer.

VOICE FROM MACHINE: Neil, this one's stuck.

NEIL DEGRASSE TYSON: Thank you.

PRINTER: You're welcome.

NEIL DEGRASSE TYSON: Well, here's a scientist who wants to
change things. She's working hard to design machines that are so much like us,
we might even consider them our friends.

PRINTER: Friends.

NEIL DEGRASSE TYSON: This is Leonardo, and today is his annual
checkup, or maybe I should say tune-up.

RICHARD LANDON (MIT): A little of both.

CYNTHIA BREAZEAL: It's both. It's a checkup and a tune up. Yeah.

NEIL DEGRASSE TYSON: You see, Leonardo is a robot, but the
engineer who designed him thinks of him as much more than a machine.

CYNTHIA BREAZEAL: Do we have the tongue again? Where's Jessie?
Jessie?

NEIL DEGRASSE TYSON: Cynthia Breazeal thinks of him as a
"creature."

CYNTHIA BREAZEAL: And does the nose wrinkle?

It's ready to go.

Okay, cool.

NEIL DEGRASSE TYSON: That's because, when Leonardo's been put
back together and has his fur coat on, he's what you call a "sociable
robot,"...

MATT BERLIN: Hello, Leo. Can you hear me?

NEIL DEGRASSE TYSON: ...a new breed of robot that Cynthia and
her students are designing, in the Robotic Life lab at MIT.

CYNTHIA BREAZEAL: This is the most amazing place you can imagine.

MATT BERLIN: It's like working in Santa's workshop.

Leo, this is Elmo. Can you find Elmo?

NEIL DEGRASSE TYSON: Cynthia's goal is to make robots that
aren't just smart, but that can learn the way people do, communicate the way
people do, even become our friends.

CYNTHIA BREAZEAL: What does it really mean to design a robot that
understands and interacts and treats people as people?

NEIL DEGRASSE TYSON: If anyone can answer this question, it'll
be Cynthia Breazeal.

BOBBY BLUMOFE (Cynthia Breazeal's husband): She's fearless, so
she tries anything. And she just seems to have no concern, whatsoever, that it
might fail. She just does it. And I can't think of any cases where it actually
has failed.

CYNTHIA BREAZEAL: If you look at the field of robotics today, you can
say robots have been in the deepest oceans, they've been to Mars, you know?
They've been all these places, but they're just now starting to come into your
living room. Your living room is the final frontier for robots.

NEIL DEGRASSE TYSON: That's because the living room is not an
easy place for a robot to exist.

After all, robotic vacuums, like this one, that are supposed to clean your
house by themselves, can't tell the difference between a chair leg and a human
leg. They're just things to avoid, or, in this case, escape from.

But for robots to become more than just tools, for them to become our
partners, as Cynthia hopes, they need the same social skills as people,
including emotion.

CYNTHIA BREAZEAL: Through our evolution, we're so specialized for social
interaction. So, if you can really design robots that can interact with people,
in this very natural, interpersonal way, I think that would be great. You
wouldn't have to have people read manuals, in order to operate them. They'd be
able to just interact with a robot the way that they would want to, which we
think will be as people interact with other living things.

NEIL DEGRASSE TYSON: But wait a minute.

ANTHONY DANIELS As Voice of C3PO From Star Wars: I've had just
about enough of you.

NEIL DEGRASSE TYSON: Robots with emotion? Isn't that just
something from the movies?

In Cynthia's case, that's exactly where it started.

CYNTHIA BREAZEAL: I was about 10 years old, and I saw the first Star
Wars movie.

ANTHONY DANIELS As Voice of C3PO From Star Wars: Excuse me, sir,
but that R2 unit is in prime condition, a real bargain.

CYNTHIA BREAZEAL: You saw R2D2 and C3PO, and it was, like, that is the
coolest thing I've ever seen.

CYNTHIA BREAZEAL: R2D2 and C3PO were really kind of your, your
sidekicks. They were really kind of your, your friends.

BOBBY BLUMOFE: That was really sort of the beginning of her inspiration
to do what she does now.

NEIL DEGRASSE TYSON: The daughter of two scientists, Cynthia
had robots on the brain, and in third grade in Livermore, California, she wrote
a story that was strangely prophetic.

CYNTHIA BREAZEAL: I talked about this robot that stole huckleberry pies,
that apparently was a robot that was created by the Klingon Empire. The last
sentence, I think, was perhaps the most salient, which is, "And its feelings
run on a computer." So, I mean, even then, it was just kind of a given for me
that robots would have emotions and feelings.

NEIL DEGRASSE TYSON: Her teacher's only comment: "Proofread
next time."

Cynthia's passion for robots soon switched to sports.

BOBBY BLUMOFE: She was actually a fairly accomplished tennis
player...soccer and all these things, growing up. That took me by surprise. I
hadn't really expected that she was such a jock. I would have expected, maybe,
more of an egghead.

NEIL DEGRASSE TYSON: Well, she did wind up at MIT, where she
studied electrical engineering and computer science with Rodney Brooks, who was
designing robots inspired by living, breathing creatures.

RODNEY BROOKS (Massachusetts Institute of Technology): Cynthia
came to my lab just a little while after we'd started building robots based on
insects.

CYNTHIA BREAZEAL: And I thought, you know, if we are ever going to see
those robots that we saw in Star Wars in the real world, it's going to
start in a place like this.

NEIL DEGRASSE TYSON: With Brooks, she built a robotic bug
named Attila, and then moved up the food chain to working on a humanoid robot
called Cog, who was strangely adept at playing with Slinkys®.

RODNEY BROOKS: When we first thought about Cog, we thought about the
all-intelligent robot that was going to be able to manipulate the world and do
things. We weren't thinking about how it was really going to interact with
people.

NEIL DEGRASSE TYSON: But Cynthia wanted to make a robot you
can relate to, a robot that would learn because people would want to teach
it.

MATT BERLIN: She has a vision of robots: that you build them starting
with the social interaction, and you build the intelligence out from that.

RODNEY BROOKS: Cynthia came up with the phrase "appliance or friend."

NEIL DEGRASSE TYSON: But how do you make a robot that's more
friend than appliance?

Long before Cynthia had her own kids, Ryan and Nathan, she hit on an idea:
what if you could get people to relate to a robot in the same way a parent
relates to a child?

CYNTHIA BREAZEAL: If you look at the way an adult interacts with an
infant or a very young child, you, fundamentally, have this highly
sophisticated being interacting with an immature version of it. But yet you
could still have a very genuine interaction. So, we leverage that, in building
these robots that are also very youthful in their nature.

It's a little trickier with the robots, because the robots, of course, don't
have these wonderful little brains and bodies that infants have, you know? It's
a sort of very low-pass, kind of crude approximation of that.

NEIL DEGRASSE TYSON: Beginning in the late 1990s, Cynthia
rolled up her sleeves and got out the toolkit to build a new kind of robot,
based on theories of child development.

RODNEY BROOKS: She's willing to have way out ideas and pursue them. At
the same time, she will delve into any technology, to put all the pieces
together to make it happen.

NEIL DEGRASSE TYSON: What she came up with was a robotic head
named Kismet, with baby-like features, such as prominent eyes, to draw people
into a social relationship.

WOMAN : You're such a cute little robot.

NEIL DEGRASSE TYSON: She programmed Kismet to analyze the
emotional intent of the person speaking to it, based on the pitch and intensity
of their voice.

WOMAN: No.

NEIL DEGRASSE TYSON: Then, all on its own, Kismet computed the
right emotional response, which it expressed in its face and posture and voice.

CYNTHIA BREAZEAL: People very quickly would become enamored and attached
to the robot. But you almost can't help it, because it was really adorable.

MAN: Kismet, I think we've got something going on here, you and me.

RODNEY BROOKS: Cynthia managed to get this being with a presence. Before
Cynthia's work with Kismet, the question was, "How does the robot react to the
world?" What Cynthia brought was, "How do people react to the robot?"

NEIL DEGRASSE TYSON: Overnight, Kismet and Cynthia were
superstars.

The name Kismet means "fate" in Turkish. And, around this time, Cynthia
sent a fateful email to someone she had met a few years before.

BOBBY BLUMOFE: And the email is basically, you know, "Hi, it's Cynthia.
Do you remember me?" Which I thought was kind of a funny thing, because of
course I remembered her.

NEIL DEGRASSE TYSON: Cynthia and Bobby were eventually
married, but not before Hollywood called.

Stephen Spielberg was just finishing the movie A.I., a futuristic
tale about the day scientists would program robots with the ultimate human
emotion.

WILLIAM HURT (As Professor Hobby, from A.I./Film Clip):
Tell me, what is love?

CYNTHIA BREAZEAL: I met with Steven Spielberg and gave him a little
primer on A.I. and met Stan.

He had made all the robots for A.I., including a bear that befriends humans
and has emotions.

WOMAN from AI/Film clip: His name is Teddy.

CYNTHIA BREAZEAL: I told Stan that we should build Teddy, but we should
really build Teddy.

JACK ANGEL (As Voice of Teddy from A.I./Film Clip): I am
not a toy.

NEIL DEGRASSE TYSON: The result of their collaboration was the
robot called Leonardo.

CYNTHIA BREAZEAL: Of course, it's after Leonardo da Vinci, not Leonardo
diCaprio, which some people ask me.

NEIL DEGRASSE TYSON: It's a million dollar creature with a
body by Stan and brains by Cynthia.

Cynthia and her students are using Leonardo to explore how robots can learn and
communicate with people in everyday situations.

MATT BERLIN: Leo, this is Cookie Monster. Leo, can you find Cookie Monster?

NEIL DEGRASSE TYSON: To create a life-like, face-to-face
interaction with people, software allows Leo to track the head of the person
speaking to him. Then he stores the name and color and shape of the object in
his memory.

MATT BERLIN: Very good, Leo. Leo, this is Elmo. Can you find Elmo?

NEIL DEGRASSE TYSON: Leo can also use what he learns to think
for himself. When Matt tries to trick him...

MATT BERLIN: Can you find Elmo?

NEIL DEGRASSE TYSON: ...Leo catches on quickly, responding
with a shrug and even a puzzled look.

Cynthia believes this kind of natural communication between people and
machines is essential for robots to become part our daily lives.

DAN STIEHL (Massachusetts Institute of Technology): Cynthia's one
of the best people in the world, in terms of human-robot interaction, and
really understanding that it's much more than a person just pressing buttons on
a machine, but really having the machine be engaging and improving that overall
interaction.

NEIL DEGRASSE TYSON: The team's latest robot is a teddy bear
called "the Huggable." Inspired by pet therapy, it may one day act as a
companion for kids in the hospital, as well as assist their caregivers. With
skin that's sensitive to touch and temperature, it's designed for physical,
full-body interaction with humans.

JUSTIN KOSSLYN (Yale University): This guy has a motion
classifier in him, which means he knows how he's being moved. So I can do some
stuff, like bouncing him, and you can see on the screen how he's responding:
pretty psyched about that. He can also respond to...if I want to be kind of
evil, maybe some shaking. Grrr. And it made him sad; that was mean.

When he's used in hospitals, if a kid were to shake him, like I just did, the
nurse's station could get a little message saying, "You may want to check in on
Room 44."

And the last thing this guy will do is, if I put him down, he knows he's not
moving anymore, and so he's going to respond by saying goodbye. Yep. Bye
bye.

CYNTHIA BREAZEAL: Ooh, you got some fancy moves there.

NEIL DEGRASSE TYSON: But will we ever have an interaction with
a robot that's as genuine as this? And if so, would that be a good thing?

CYNTHIA BREAZEAL: If I really didn't believe that we would have better
living with robots, that robots could really be a technology that enhanced and
complemented our lives, like, I mean, the way that...same reason we create any
other technology, I certainly wouldn't be doing it.

BOBBY BLUMOFE: Maybe Nathan and Ryan could be among the first kids to
grow up with robots that go beyond just the notion of a vacuum cleaner, but
actually socially and emotionally engaging and interactive robots... thatwould be pretty cool!

CYNTHIA BREAZEAL: I do think, in time, people will have, sort of,
relationships with certain kinds of robots—not every robot, but certain
kinds of robots—where they might feel that it is a sort of friendship,
but it's going to be of a robot-human kind.

PAPYRUS

NEIL DEGRASSE TYSON: When I was a kid, I used to play this
game, Password(TM). And the secret password is always
invisible, hidden until you slid the paper into this sleeve, and then the
secret word is revealed.

Well, what if the secret words aren't part of a kids' board game, but
instead are on a crumbling, ancient manuscript?

Correspondent Beth Nissen caught up with investigators who are uncovering
secret messages that have stayed hidden for 2,000 years.

BETH NISSEN (Correspondent): In these vaults, on these
shelves, in these boxes at Oxford University, ancient clues—2,000 years
old—to a glorious human past; wrapped in printed paper, fragments of
ancient paper, pieces of the D.N.A. of Western Civilization.

ROGER T. MACFARLANE (Brigham Young University): Here's one that
contains a large page of Homer's Odyssey, still with quite a bit of mud
and sand clinging to it.

BETH NISSEN: These are only a few of the faded fragments found
buried near the outskirts of what was, at around the turn from B.C. into A.D.,
a mid-sized capital city in Greek-ruled Egypt, the city of
Oxyrhynchus—actually, found buried in the Oxyrhynchus city dump, in
rubbish mounds.

ROGER MACFARLANE: There can be more Homer, new pieces of Sophocles,
Euripides, other authors who were being read in antiquity. You never really
know what's going to come out of the box.

BETH NISSEN: Yet somehow, buried above the water tables and
beneath the dry sands of Egypt, for all those centuries, almost half a million
of these papyri fragments survived, these pieces of ancient paper made from
papyrus.

JOSHUA SOSIN: Papyrus is a plant. It is a reed that grows almost
exclusively along thebanks of the Nile. You shave the stalk into thin
strips, lay them parallel to each other, lay strips running perpendicular to
them; you pound it or press it, such that the cell walls break down. Cellulose
seeps out, creating a kind of gooey natural glue that binds the strips
together, which can then be pressed, polished and written on. The stuff is
really quite durable, in a way, more durable than the paper you're used to
taking notes on today.

BETH NISSEN: The tons of this reedy paper found at Oxyrhynchus
documented the daily life of an ancient city's markets and businesses and
courts.

JOSHUA SOSIN: We have marriage contracts, divorce contracts, tax
declarations, census registers, hate mail, dinner invitations. We have
letters-home-to-Mom. You name it, we have it on papyrus.

BETH NISSEN: Thousands more of the Oxyrhynchus fragments were
unreadable, soiled, grimy.

BENJAMIN HENRY (The University of Texas at Austin): Because this
was a rubbish dump, things get charred—if burning waste was put on top of
them —or stained.

BETH NISSEN: Or, like this fragment, which looks, at first,
like the work of, say, Jackson Pollack of Crete. The only readable word of
Greek is just visible at the very bottom. You can read "Christos."

BENJAMIN HENRY: Yeah, there's "Christos," kind of a row sigma with a bar
above it. So that's the abbreviation for "Christos," you know it's a Christian
text. But much of it is totally illegible.

BETH NISSEN: And papyrologists assume there are letters there.
Papyrus was too expensive to throw away unused and often had writing on both
sides. But texts like this were a tantalizing, frustrating mystery.

BENJAMIN HENRY: Really, you're never going to be able to publish a text
like this. You can look at that under the microscope as much as you like, but
it's just a complete mess.

BETH NISSEN: What papyrologists really needed was
this—an equivalent to Superman's x-ray vision—a way to see through
whatever was on the surface of papyri—ancient food stains, burn marks,
mummy paint—see through to the writing underneath.

As the ancient Greek scientist Archimedes is said to have said from his
bath: Eureka!

It's called multispectral imaging, a technology developed by NASA to "see
through" clouds of gas in space.

ROGER MACFARLANE: It was a significant step forward, when a scholar at
NASA's Jet Propulsion Laboratory decided to apply the technology to texts.

BETH NISSEN: Ancient texts, written on papyri.

The project today: see if multispectral imaging can help scholars at the
University of California at Berkeley read part of an account of the Trojan War,
by the poet Dictys of Crete, a part obscured by a large reddish stain.

ROGER MACFARLANE: Some people think it's a spill, a chemical spill
perhaps, or a spot of wine that was dropped on it. Even the best papyrologists
who've worked on this are usually not able to pick out any more than a few
scattered letters in here, and even at that, they feel like they're
guessing.

BETH NISSEN: The fragile fragment is put on a moving imaging
bed under a scientific-grade digital camera, which captures high-definition
images of the fragment, through a succession of color filters, one filter at a
time, a dozen different filters in all.

ROGER MACFARLANE: Each individual filter allows only a certain portion
of the light spectrum through.

BETH NISSEN: The light in the range of the spectrum visible to
the naked eye, reflects off whatever is on the surface of most of the papyri
pieces, the stains, dirt, mummy paint, whatever. The camera can't see much more
through these filters than the eye can, which isn't much.

But results tend to be better, using the filters that let in the range of
the light spectrum the human eye cannot see.

ROGER MACFARLANE: I've seen the best results in the infrared at 950
nanometers.

BETH NISSEN: Light in the infrared part of the spectrum,
invisible to the naked eye but not the camera, is more likely to pass through
what's on the papyrus surface to the ink underneath. Surface stains and dirt
fade away. The inked letters appear; black magic.

BENJAMIN HENRY: Ink, which is pretty much pure carbon—it's made
out of soot mixed with glue—will absorb all of the infrared, and so it
will come out black.

BETH NISSEN: Every time they see this 21st century technology
work on first or second century fragments, papyrologists are thrilled, or as
thrilled as papyrologists get.

ROGER MACFARLANE: None of us is really inclined to give high-fives and
celebrate too much, but we were really pleased.

BETH NISSEN: They've been pleased with multispectral imaging
at Oxford, too— home of the world's largest collection of ancient papyri:
all those fragments excavated from the Oxyrhynchus city dump.

They have as many as 500,000 fragments, but only about one percent have
been read and published by the few scholars working on them. Uncounted
thousands are illegible, in shreds, soiled.

BENJAMIN HENRY: There are fragments there that we'd pretty much
completely given up all hope of ever being able to read.

BETH NISSEN: Like that Jackson Pollack-y fragment that had the
word "Christos" on it.

BENJAMIN HENRY: We put it under the multispectral imaging camera, and,
all of a sudden, the background completely drops out, and wherever there was
ink, you can read the ink as clear as the day it was written.

BETH NISSEN: And what was written? A passage from the New
Testament, St. Paul's "Epistle to the Romans," Chapter 14, Verses 7-9.

BENJAMIN HENRY: And then "Eis touto gar Christos apethanen," "for this
reason did Christ die." And it is now our earliest copy for these verses. We
did have another third century papyrus of the "Epistle to the Romans," but it
actually is very fragmentary. But now, we've got a complete text of these
verses in a late second and early third, perhaps, century copy.

JOSHUA SOSIN: I don't know how long we have, until the things sitting in
shoeboxes in this or that university turn to dust, but we've got to get
rolling. There are a great many, I mean, many thousands of papyri that are
sitting in boxes in dark hallways, waiting to be read.

NEIL DEGRASSE TYSON: And now for some final thoughts on
extinction. When you look up to the sky, you see the Moon, Sun and stars, not
as they are, but as they once were. Traveling at more than 186,000 miles per
second, their light simply takes time to reach us.

From the Moon, it takes between one and two seconds; from the Sun, a little
more than eight minutes; from Alpha Centauri, the nearest star system to the
Sun, about four years; from the Andromeda Galaxy, a close neighbor
of the Milky Way, light takes more than two million years to reach
us.

So the farther away an object is, the further back in time we see it. Keep
this up, and eventually, we bear witness to the birth of galaxies and the birth
of the universe itself.

Yes, we can look into the past of distant places, but aliens within those
distant places can look our way, and bear witness to our distant past. For all
we know, light from Earth's greatest extinction episode is just now reaching
alien telescopes, perhaps prompting them to wonder, "Has Planet Earth reached a
dead end? Does life there have any future at all?" Today, with the highest rate
of species going extinct since the demise of the dinosaurs, those same
questions should perhaps occur to us, too. And that is the cosmic
perspective.

And now, we'd like to hear your perspective on this episode of NOVA
scienceNOW. Log on to our Web site and tell us what you think. You can
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Neil deGrasse Tyson is director of the Hayden Planetarium in the Rose Center
for Earth and Space at the American Museum of Natural History.

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This material is based upon work supported by the National Science Foundation
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